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Scared of messed up m140 diode

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Hey guys recently I was taking a part my laser to inspect the lens, and I think I touched the diode. Now the laser doesn't make a dot on the wall and when there is no lens it used to have a nice shape to the diode beam. Now that diffuse beam looks different and cloudy.
Please help, very nervous.
 

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ouch that is a bummer. I will pay attention to this thread so I learn what can be done to a diode window that has been touched.
good luck
 
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grainde

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I cleaned a couple of diodes the other day using a cotton bud and some isopropyl alcohol. Do this at your own risk!!!

Add a drop to the cotton bud and very, very gently wipe the window. I used the wider more padded portion on the side of the stick to do this. I then got a lens cleaning cloth and gently spun it on the window. ie touch it on there and turn the laser.

Caution do not make the stick too wet with alcohol. Do not press hard. Do not clean for too long ie saturate the diode with alcohol. Doing any of these things could loosen the diode window.

I did this on two diodes; a Pl450 and a Pl520 as their raw dots were mucky with several dots. When I was finished the raw output looked like new. Just be careful and you will be fine. :beer:
 
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Gonna give it a try...........AT MY OWN RISK!!!

EDIT:

I didn't work. Stayed the same but I can see a tiny (and I do mean tiny!) dot of something on the window. Beam specs now suck, huge fat beam, horrible burning characteristics.

Also, this diode produces a square beam so now it still has the square beam but it's speckled with messed up spots.

I really am worried I will need to buy a new m140 diode, but there $50 and that's a lot right now for me. Besides, I don't know how to dissemble it how it is.

Waiting for help!!!!!!!!
 
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grainde

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It is possible you just moved the grease, or what ever it was around the window. What exactly did you have on your fingers when you touched it? If it was some sort of grease you may have to try cleaning a little more. Did you use isopropyl alcohol, or some other alcohol like ethanol or mix like methylated spirits?

Isopropyl will be better at removing grease than the shorter chain alcohols.:beer:

Edit: to see the window clearly angle it up to the light until it reflects clearly you can then see where the grease/debris is. Also make sure you never turn the laser on until you are completely sure it is dry and nothing is on the window (using above method).
 
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I used rubbing isopropyl alcohol.

I was turned it on once to see if it was clean, because the debris is so small.
 
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grainde

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Only thing I can suggest is try again. If you dont want to risk this, perhaps you could ship it to a vet to try. Still no guarantee it will get fixed however. If it is only grease though, you should get it off using this method.

You could also try with the corner of a very clean glasses microfibre cloth...

So what did you have on your fingers and how did you actually manage to touch it inside the module?
 
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I have viewed the lens under a 30x power magnifying lens for viewing old coins. I cannot determine any dirt on the lens.

See, I'm not sure if I actually touched it myself, but I thought I might have. The module is very strange, it unscrews differently.

Here is an images of the module with the diode in the center. The dot in the middle of the dot is the diode window.

Another entire assembly screws onto the front with a 3 element lens.
 

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grainde

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Have you been testing the raw output or that with a lens? If the latter, is your lens clean?
 
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Well this is the deal. I have taken the lens off and shined just the diode. It makes a nice square on the wall. Now it does not make a nice square on the wall and when I add the lens it goes wacky too, and since it's different now even without the lens, I would guess it's not the lens, also considering the lens is encased and is pretty hard to get to in this model.
 

grainde

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Normally if the window is mucky you will see lots of artifacts. Can you take a pic of the output? Make sure first, that the dot you mentioned earlier (on the window) is gone.

Edit: When you angle the diode window to a light source you should find an angle where the whole window lights up. At this angle you should be able to inspect the window to see where the grease is and remove it with the cleaning cloth. Just make sure there are no streaks and no lines on the window; it should look homogeneous across the surface. You could also gently breathe on the window to lightly mist it and see this - just dont spit on it. ;)
 
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I'll upload an image but there is a problem. I can see something on the window that will not come off. It's so small it's hard to see, in fact, it's easier to see without the magnifying glass.

I can't tell if it's on the outside or inside, the laser is ruined an I don't know what to do.
The beam is like 1 inch at 5 inches at 20'.
 

grainde

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Without a lens this sounds ok? These are multimode diodes and the beam specs suck...

Anyway try to clean it again, if it looks like there is still muck on the window. The risk from the alcohol is that the diode window could come loose if you use too much, it wont actually damage the window. Make sure there are no hairs, or fibres from the cleaning cloth before turning on.
 
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Could smoke have caused damage to the inside of the diode window? Could it be a scratch?
 
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